1. Field of the Invention
The present invention relates to a board terminal and a board connector.
2. Description of the Related Art
Conventionally, a terminal including a base material made of Cu alloy and a Sn plating film covering a surface of the base material is known as a board terminal used for a printed circuit board. The board terminal of this type is generally held in a housing to constitute a board connector, and used by mounting the board connector on a printed circuit board or directly mounting the board terminal on the printed circuit board.
Japanese Unexamined Patent Publication No. 2003-147579 preceding the present application discloses a terminal including a plating film formed by successively laminating a Ni plating layer, a Cu plating layer and a Sn plating layer on a surface of a base material made of Cu alloy as a terminal used for various connectors. In this literature, it is described that an insertion force can be reduced at the time of connection to a mating terminal by adopting the above configuration.
Note that Publication of Japanese Patent No. 3926355 preceding the present application discloses an electrically conductive material for connection parts obtained by performing a reflow process after Cu plating and Sn plating are formed on an uneven Cu plate surface.
However, the prior art has a room for improvement in the following points. Specifically, the conventional terminal including the Sn plating film has a high friction coefficient of a Sn plating film surface due to the softness of Sn and has a problem that an insertion force increases at the time of connection to the mating terminal. Particularly, a board connector adopts a multi-pole structure using a plurality of board terminals in many cases and has a problem that an insertion force tends to increase as the number of terminals increases.
Further, the board terminal has one end connected to the printed circuit board by solder bonding in many cases. Thus, if the plating film has poor solder wettability, there is a problem that connection reliability is reduced.
The present invention was developed in view of the above background and attained with a view to providing a board terminal capable of realizing a low insertion force and having good solder wettability and a board connector using the same.